Dental filling-tool.



UNrTED Aralar FFICE.

PERRY (J. HAMMERSMITII, OF BUFFALO, NEW YORK, ASSIGNOR OF ONE- l-IALF TO FRANK S. WAHL, OF BUFFALO, NEW YORK.

DENTAL FILLING-TOOL.

erncrrrcarron fermmg pel-t er Letters retenu No. 712,526, dated November 4, 1902.

Application led July 243 1902. Serial No. 116.813. (No model.)

T0 a/ZZ whom, it muy concern:

Be it known that I, PERRY C. HAMMERSMITH, a citizen of the United States, residing at Buffalo, in the'county of `Erie and State of New This invention relates to the amalgam car-` riers or holders employed by dentists for carrying a quantity ot' amalgam to a `tooth to be filled and depositing it in the cavityl of the tooth. y

The principal object of my invention is to provide an implement of this character which permits the amalgam to be ejected from the holder into the cavity of the tooth without pressing or abutting thetool against the tooth or the gums, such pressure causing more or less discomfort and pain where the toothf un der treatment is sensitive.

My invention has the further object to so construct the tool that it can be readily dismembered for cleaning the parts of the amalgam-holder.

In the accompanying drawings, Figure l is a sectional. side elevation of the tool. Fig. 2 is a top planview thereof. Fig. 3 is an enlarged sectional elevation of the head of the tool at right angles to Fig. 1. Fig. 4 is a sectional side elevation of the head of the tool, showing a modified construction of the same.

Similar letters of reference indicate corresponding parts throughout the several Views.

The tool has a comparatively long handle A, the shank a of whichl carries at `its front end `an amalgam cylinder or tubular holder B, adapted to receive and hold a suitable quantity of amalgam or other semiplastic filling material or cement. This holder, which is preferably arranged in a forwardly-inclined position, is formed on or rigidly secured to the shank a. The upper end of the holder is closed, while its lower end is open and eX- tends laterally beyond the shank a. In this holder a plunger C is snugly fitted, the rod or stem c of which passes through an opening in the head of the holder. The upward or backward movement of the plunger is limited by the head ofthe holder, which forms a stop for arrestingthe movement of the plunger in this direction;

D isa spring which resists the forward movement ot' the plungerjand which effects its return stroke when unrestrained. In the preferred construction (shown in Figs. l, 2,

"and 3) this springis dat and its free or main portion is substantially parallel with the handle of the too-l, while its rear portion or shank d is bent inwardly at right angles to the main portion and secured to the` handle by a screw 0l or other fastening. The free front end of the spring is bent upwardslightly, as shown at d2, and passes loosely through a transverse slot e, formed in the stem of the plunger, so that the angular end of the spring is free to play in this slot in following the movements of the plunger. This spring normally holds the plunger O at the upper end of the holder B. In the `use of the implement the amalgam or other semiplastic filling material is picked up by the holder B by pressing its open'end upon a quantity of the material. The openm end of the holder is then placed over the `tooth-cavity to `be llled and the plunger depressed by means of the spring, which latter is pressed toward the handle of thetool by `the thumb or forefinger of the hand in which the tool is held. The amalgam is thereby ejected from the holder and deposited in the cavity of the tooth. Upon releasing the de- :tlected spring D the same returns to its former position and draws the plunger to the top of the holder preparatory to again filling the latter with amalgam. The spring is preferably comparatively long, asshown, so that its rear end is remote from the plunger, this construction enabling the plunger to be conveniently operated in using the tool on back teeth.

In ejecting the amalgam from the holder into the tooth-cavity it is not necessary to press the holder against the tooth, but the holder is simply held over or opposite the cavity withoutpressure upon the tooth and the plunger is depressed in the holder. The patient, therefore', experiences no pain or discomfort from the use of the tool.

The plunger can be readily removed from the holder for cleaning the parts by unserewing the spring D from the handle, Withdrawing its free end from the slot of the plunger, and then removing the latter through the open lower end of the holder.

In the modification of the tool shown in Fig. 4 the amalgam-holder and the plunger are Constructed as in the rst-described implement; but a spiral retraoting-spring D is substituted for the flat spring. In this case the spiral spring surrounds the plunger-stem.

and bears at its lower end against the head of the holder and at its upper end against a button f on the stem.

I claim as my inventionl. A dental filling-tool, Consisting of a handle or shank, an amalgam holder or cylinder rigidly mounted on the handle and open at one end, a plunger movable in the holder, and a spring arranged to retract the plunger, substantially as set forth.

2. A dental filling-tool, consisting of a handle or shank, an amalgam -holder rigidly mounted on the end of the handle in a forvwardly-inelined position, said holder being closed at its upper end and open at its lower end,'a plunger movable in said holder and having a stem which extends through the closed end of the holder and which is provided With a transverse slot, and a at retraeting-spring arranged substantially parallel with the handle and provided at its rear end with a transverse shank which is secured to the handle and having its front end bent at an angle to its body portion and arranged in the slot of the plunger-stem, substantially as set forth.

Witness my hand this 18th day of July, 1902.

PERRY C. HAMMERSMITH. Witnesses:

A. C. TRAUT,

ELLsWoR'rH J. RICHARD. 

